From the few that have actually tried it, it appears to work. But the results are varied some seem to be fully functional others not
You know similar stuff has been getting done with graphics cards for years...you could bios flash an x1800pro to open up more pipelines and turn it into an x1800xt for example.
I'm not saying I believe this...but if it's true then jesus AMD have been very, very smart because this is the sort of 'news' that will sell millions more 720 BE's 😛